1. Field of the Invention
This invention relates to a process for producing .beta.-(sec-alkoxy) ethanol of the general formula R.sub.1 R.sub.2 CHOCH.sub.2 CH.sub.2 OH from olefins and glycol.
2. Background of the Invention
Secondary alcohol ethoxylates are used as industrial detergents. A precursor of the secondary alcohol ethoxylate is .beta.-(sec-alkoxy) ethanol from which the sec-alcohol ethoxylate can be made by conventional base catalyzed ethoxylation.
U.S. Pat. No. 2,067,385 issued Jan. 12, 1977, to Evans et al discloses the reaction of olefins with alcohols in the presence of strong acid catalysts such as sulfuric acid and benzene sulfonic acids. No particular effects of solvents are noted.
Netherlands Pat. No. 111,292 discloses the reaction of olefins with polyhydroxy compounds in the presence of acid catalysts such as BF.sub.3, sulfuric acid, and aromatic sulfonic acids. The use of a polar solvent is disclosed such as sulfolane. No particular effects of one phase operation are noted.
The use of sufficient sulfolane type solvent to provide the phase operation provides enhanced rates of conversion. One phase operation, however, requires the use of relatively large amounts of solvent which must be removed from the product. Traditional methods for removing the sulfolane type solvents are impractical or extract tremendous economic penalties. The high boiling point of the sulfolane-type solvents (280.degree. C. for sulfolane) can result in product decomposition if distillation is utilized especially over long time periods. Cooling the solvent-containing product to obtain phase separation is possible, but because of the larger amount of solvent used, a large heat cycle is involved which would extract a large economic penalty. Alternatively, water could be added to the cooled product mixture to enhance partitioning. But here an economic disadvantage arises from the need to cool and the need to remove the added water from the recycle stream. On the other hand, the use of a small amount of a paraffinic type solvent allows for high product recoveries at the same temperature as the reaction operates, thus minimizing heat load and product decomposition.